19708529957 has 2 divisors, whose sum is σ = 19708529958. Its totient is φ = 19708529956.

The previous prime is 19708529923. The next prime is 19708529987. The reversal of 19708529957 is 75992580791.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12135005281 + 7573524676 = 110159^2 + 87026^2 .

It is an emirp because it is prime and its reverse (75992580791) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19708529957 - 2¹⁰ = 19708528933 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19708529957.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19708529917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9854264978 + 9854264979.

It is an arithmetic number, because the mean of its divisors is an integer number (9854264979).

Almost surely, 2^19708529957 is an apocalyptic number.

It is an amenable number.

19708529957 is a deficient number, since it is larger than the sum of its proper divisors (1).

19708529957 is an equidigital number, since it uses as much as digits as its factorization.

19708529957 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14288400, while the sum is 62.

The spelling of 19708529957 in words is "nineteen billion, seven hundred eight million, five hundred twenty-nine thousand, nine hundred fifty-seven".